1. Field of the Disclosure
The disclosure relates to a touch display; more specifically, the disclosure relates to an optical touch display, a calibration apparatus, and a calibration method thereof.
2. Description of the Related Art
Because of developments in technology and trends in the commercial market, electronic devices controlled by touch have become more and more commonplace. Due to the restriction of manufacturing costs and the efficiency, both resistive touch panels and capacitive touch panels can only be applied to small size devices such as cell phones. Nowadays, large touch displays are usually optical touch displays, using photo sensors. Optical touch displays are one fairly competitive type of large size touch display because of the low manufacturing cost and the high touch accuracy.
The principle of optical touch displays is to detect a location of fingers and then transform the location into a screen position to implement the touch feature; consequently, constructing a transformation mechanism is essential for optical touch displays. Larger touch displays require more calibration points to ensure detection accuracy. However, having more calibration points also increases the calibration time and number of steps. As a result, the calibration time and necessary labor are significantly increased, especially during mass production. These increases make the production of such devices less economical. Thus, there is a need to provide a new calibration method for optical touch displays using fewer calibration points and requiring less calibration time to meet the best calibration requirements to obviate the problem of the prior art.